The present invention relates, in general, to optical parametric oscillators, and more particularly, to a broadly tunable optical parametric oscillator which is tunable in the visible and in the near infrared.
Low-temperature phase barium metaborate (.beta.-Ba.sub.2 O.sub.4) is a newly discovered nonlinear optical material which holds much promise in frequency conversion applications, as described in U.S. patent application Ser. No. 373,064, filed June 26, 1989 and assigned to the assignee of the present application, now abandoned and replaced by FWE Ser. No. 07/581,090, filed Sept. 11, 1990. Particularly attractive properties of beta barium metaborate are its broad transparency, large optical nonlinearity, large birefringence, high optical damage threshold, and large fracture temperature. Applications such as the generation of efficient coherent ultraviolet light, high average power frequency conversion and frequency doubling of ultrashort pulses benefit from these properties.
There remains, however, a continuing need for light sources at wavelengths in the visible and near infrared which incorporate suitable characteristics such as tunability so as to permit the study of numerous ultrafast phenomena which have heretofore been inaccessible to direct optical study. Of particular value for many uses are light sources which are tunable through a broad range.